Among the 19th-century economists, the capital designated only that of business wealth that was the product of past . Wealth that is not produced, such as land or ore , was excluded from the definition. Income from (so defined) was called profit, or interest, the income from natural resources was called rent. economists, for whom capital means simply the of goods and monies used to produce more goods and monies, no longer make this .
The forms of capital can be distinguished in various ways. One common distinction is between fixed and capital. Fixed capital includes all the more or less durable means of production, such as land, buildings, and . Circulating capital refers to nonrenewable goods, such as raw materials and , and the funds required to pay wages and other claims against the .